CY8C21334_13 Datasheet, PDF (35/38 Pages) Cypress Semiconductor – Automotive – Extended Temperature PSoC® Programmable System-on-Chip™

CY8C21334, CY8C21534
Glossary (continued)
SRAM
An acronym for static random access memory. A memory device where you can store and retrieve data at a high
rate of speed. The term static is used because, after a value is loaded into an SRAM cell, it remains unchanged
until it is explicitly altered or until power is removed from the device.
SROM
An acronym for supervisory read only memory. The SROM holds code that is used to boot the device, calibrate
circuitry, and perform flash operations. The functions of the SROM may be accessed in normal user code,
operating from flash.
stop bit
A signal following a character or block that prepares the receiving device to receive the next character or block.
synchronous
1. A signal whose data is not acknowledged or acted upon until the next active edge of a clock signal.
2. A system whose operation is synchronized by a clock signal.
tri-state
A function whose output can adopt three states: 0, 1, and Z (high-impedance). The function does not drive any
value in the Z state and, in many respects, may be considered to be disconnected from the rest of the circuit,
allowing another output to drive the same net.
UART
A UART or universal asynchronous receiver-transmitter translates between parallel bits of data and serial bits.
user modules
Pre-built, pre-tested hardware/firmware peripheral functions that take care of managing and configuring the lower
level analog and digital PSoC blocks. User modules also provide high level API (Application Programming
Interface) for the peripheral function.
user space
The bank 0 space of the register map. The registers in this bank are more likely to be modified during normal
program execution and not just during initialization. Registers in bank 1 are most likely to be modified only during
the initialization phase of the program.
V_DD
A name for a power net meaning “voltage drain.” The most positive power supply signal. Usually 5 V or 3.3 V.
V_SS
A name for a power net meaning “voltage source.” The most negative power supply signal.
watchdog timer A timer that must be serviced periodically. If it is not serviced, the CPU resets after a specified period of time.
Document Number:38-12038 Rev. *J
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